Wireless communications systems are widely deployed to provide, for example, a broad range of voice and data-related services. Typical wireless communications systems consist of multiple-access communication networks that allow users to share common network resources. Examples of these networks are time division multiple access (“TDMA”) systems, code division multiple access (“CDMA”) systems, single carrier frequency division multiple access (“SC-FDMA”) systems, orthogonal frequency division multiple access (“OFDMA”) systems, etc. or other like systems. An OFDMA system is supported by various technology standards such as evolved universal terrestrial radio access (“E-UTRA”), Wi-Fi, worldwide interoperability for microwave access (“WiMAX”), ultra mobile broadband (“UMB”), etc. and other similar systems. Further, the implementations of these systems are described by specifications developed by various standards bodies such as the third generation partnership project (“3GPP”) and 3GPP2.
Communications between user equipment and base stations may be established using single-input, single-output systems (“SISO”), where only one antenna is used for both the receiver and transmitter; single-input, multiple-output systems (“SIMO”), where multiple antennas are used at the receiver and only one antenna is used at the transmitter; and multiple-input, multiple-output systems (“MIMO”), where multiple antennas are used at the receiver and transmitter. Compared to a SISO system, SIMO may provide increased coverage while MIMO systems may provide increased spectral efficiency and higher data throughput if the multiple transmit antennas, multiple receive antennas or both are utilized.
In many modern communication systems such as SIMO and MIMO, coding techniques are used to transmit signals from a user equipment or handset. However, these coding techniques add complexity to a wireless system and make recovery of a wireless transmission difficult at the receiver. Simplification of the coding and decoding techniques, while still maintaining robustness of signal transmission and security is therefore desired. Further, such simplification reduces the power necessary to operate these systems thus extending the life and/or increasing the range of such systems.
Skilled artisans will appreciate that elements in the accompanying figures are illustrated for clarity, simplicity and to further help improve understanding of the embodiments, and have not necessarily been drawn to scale.